Answer:
Strontium
Explanation:
In the periodic table, an element with two (2) valence electrons is found on group 2. Group 2 is a group of the periodic table that harbors element called ALKALINE EARTH METALS. As the name implies, they are metals that possess shiny and solid characteristics at room temperature.
Group 2 elements include the following: Beryllium (Be), Magnesium (Mg), Calcium (Ca), Strontium (Sr), barium (Ba), and radium (Ra). Based on the descriptive information in this question, the element being described is a GROUP 2 element. Based on the elements in the option, only STRONTIUM (Sr) is a group 2 element.
Electron structure of sodium:
₁₁Na: 1s²2s²2p⁶3s¹
Answer:
Deletion
Explanation:
A mutation refers to a change in the DNA sequence. This means that the original sequence of bases in the DNA has been altered permanently.
There are three types of DNA mutations; base substitutions, deletions and insertions.
In the particular case of this question, the original is TTCGATA while the copy is TTGATA. If you look closely at the two, you will notice that the C has been omitted. This is an example of deletion.
Answer:
because too much can neutralise the results
